The present invention relates to systems and methods for controlling engine speed of an internal combustion engine.
Electronically controlled internal combustion engines have a wide variety of applications which may include driving various machinery including pumps, for example. Diesel engines are often used to provide motive power to vehicles or vessels, in addition to powering auxiliary equipment using a power take-off (PTO) mode of operation and appropriate couplings which may include a geared transmission. Engines may also be used in stationary applications for powering generators, driving irrigation pumps, driving compressors, or in petroleum drilling applications, for example.
In one particular application, diesel engines have been used to power petroleum mud pumps which are used to supply fluid to a drilling bit when a well is being drilled. The drilling rig operator will carefully adjust the engine speed to achieve a desired pumping rate, typically using a hand throttle potentiometer. The optimum speed typically varies from job to job and may vary depending upon the characteristics of the area being drilled. Once the operator has dialed-in the appropriate speed, the engine continues driving the pump at that speed until a new section of drilling pipe must be added. At that point, the operator brings the engine back to idle and disengages the transmission or clutch to allow a new section of pipe to be threaded in place. After adding the new section of pipe, the operator must then gradually increase the engine speed and pumping rate to again dial-in the optimum speed for the current conditions. While stationary engines may be equipped with a constant speed/cruise control function, they do not allow resuming to a preselected engine speed from idle operation.
An object of the present invention is to provide a system and method for controlling an engine which provides the ability to automatically return to a selected engine speed from idle or near idle.
Another object of the present invention is to provide a system and method for controlling a diesel engine utilized in a pumping application to return to an operator selected set speed after running at an alternate or high idle speed.
A further object of the present invention is to provide a system and method for controlling an engine used in a petroleum drilling application to allow operators to return to a previously dialed-in engine speed after adding or changing pipe.
Yet another object of the present invention is to provide an engine with a cruise control function capable of resuming to a previously selected set speed from idle or near idle.
A still further object of the present invention is to provide a system and method for controlling an engine in a pumping application with throttle controls positioned at multiple locations such that the engine returns to a previously selected set speed from idle or near idle operation.
In carrying out the above objects and other objects, features, and advantages of the present invention, a method for controlling an engine used for a pumping application includes adjusting a throttle to select a desired engine speed, storing the desired engine speed in memory, reducing the engine speed to a speed at or near idle, and automatically returning the engine speed to the stored desired engine speed from idle or near idle.
A system for controlling an engine used in a pumping application includes at least one throttle to select a desired engine speed, at least one switch to indicate that the selected engine speed should be stored, at least one switch to indicate that the engine speed should be controlled to a previously stored engine speed, and an engine controller in communication with the switches and the at least one throttle, the engine controller operative to control the engine speed based on inputs received from the at least one throttle and the switches to control the engine speed to a previously stored engine speed from idle or near idle.
In one embodiment, at least two throttle controls are provided to remotely control the engine speed from corresponding control stations. The throttle controls may be any of a number of types including hand-operated, foot pedals, etc.
The present invention provides a number of advantages. For example, the present invention allows an operator to carefully select an operating speed for the engine for a particular application or operating condition, return the engine to idle, and subsequently automatically return to the previously selected engine speed from idle or near idle without further readjustment. In petroleum drilling applications, the present invention allows the operator to dial-in an appropriate speed for current conditions, return the engine to idle or near idle while adding or changing pipe, and return to the previously dialed-in engine speed without further adjustments using the throttle.
The above advantages, and other advantages, objects, and features of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings.